From the Guidelines
Acute Kidney Injury (AKI) due to hydronephrosis is primarily caused by postrenal obstruction, which leads to increased pressure in the collecting system, resulting in decreased glomerular filtration rate and kidney function. The management of AKI due to hydronephrosis requires prompt identification and relief of the obstruction, typically through urinary catheterization or nephrostomy tube placement 1. According to the American College of Radiology, the prevalence of hydronephrosis is low, ranging from 5% to 10%, with obstruction being the cause of AKI in less than 45.2% of patients with hydronephrosis 1.
Causes of AKI due to Hydronephrosis
- Postrenal obstruction, which can be caused by various factors such as kidney stones, tumors, or retroperitoneal fibrosis
- Urinary tract obstruction, which can lead to increased pressure in the collecting system and decreased kidney function
- Other causes, such as a distended bladder, reflux, pregnancy, postobstructive dilation, or diuresis, which may cause ureteral and collecting system dilatation 1
Management of AKI due to Hydronephrosis
- Prompt identification and relief of the obstruction through urinary catheterization or nephrostomy tube placement
- Urgent urological consultation for placement of ureteral stents or percutaneous nephrostomy tubes in cases of upper urinary tract obstructions
- Bladder catheterization for lower tract obstructions, such as prostatic hyperplasia or urethral strictures
- Initial assessment, including renal ultrasound to confirm hydronephrosis, measurement of post-void residual volume, and laboratory tests, such as serum creatinine, electrolytes, and urinalysis 1
- Supportive care during treatment, including careful fluid management, electrolyte monitoring, and treatment of any underlying infection with appropriate antibiotics if pyonephrosis or urinary tract infection is present 1
Importance of Rapid Intervention
The longer the obstruction persists, the greater the risk of permanent kidney damage, making rapid intervention crucial 1. After relief of obstruction, patients may experience post-obstructive diuresis, requiring close monitoring of fluid status and electrolytes to prevent dehydration and electrolyte abnormalities 1.
From the Research
Cause of Acute Kidney Injury (AKI) due to Hydronephrosis
- Hydronephrosis is a condition where the kidney swells due to the accumulation of urine, caused by an obstruction in the urinary tract 2, 3.
- The obstruction can be due to various conditions such as retroperitoneal fibrosis, malignant disease, or other factors that cause compression of the ureters 2.
- Hydronephrosis can lead to post-renal acute kidney injury (AKI), which is a reversible cause of AKI if promptly managed 2, 3.
Management of AKI due to Hydronephrosis
- The management of AKI due to hydronephrosis involves the relief of the obstruction, which can be achieved through ureteric stenting or percutaneous nephrostomy 2, 4.
- Supportive treatment, including the correction of metabolic abnormalities and fluid management, is also crucial in the management of AKI due to hydronephrosis 3.
- In some cases, renal replacement therapy may be required to support the patient's renal function until the obstruction is relieved and kidney function recovers 3.
- Early recognition and management of AKI due to hydronephrosis are critical to prevent long-term kidney damage and improve patient outcomes 5, 6.
Clinical Presentation and Diagnosis
- The clinical presentation of AKI due to hydronephrosis may include oliguria/anuria, abdominal pain, signs of retention such as edema or pleural effusion, and nausea/vomiting 2.
- Imaging studies such as tomography or ultrasound can help diagnose hydronephrosis and identify the underlying cause of the obstruction 3.
- A complete medical history and physical examination are essential in diagnosing AKI due to hydronephrosis and guiding management decisions 3.